He is an ordinary school teacher with no titles or titles. But in his teaching baggage there are more than a dozen books: textbooks, problem books that help not only understand, but even love mathematics - algebra and geometry. To the question "What is the topic of an open lesson?" He replies: "I don't know. I'll improvise." He drinks coffee during class! And his students do not notice this - everyone is immersed in solving problems. Blessed is the class that has such a Master! Read the book and see for yourself.